The present invention relates in general to a quick connector including a tubular male element which has an annular protrusion portion formed on an outer circumferential surface of an introduced end portion of the male element and spaced apart form an axial end of the male element by a predetermined distance, and a tubular female element which has in its axially opposite end portions an opening portion into that the tubular male element is introduced whereby the tubular male and female elements are connected to each other.
Conventionally, as this kind of quick connectors, there have been proposed various ones having respective constructions. For example, in a quick connector as disclosed in JP-A-03-219189 and U.S. Pat. No. 5,154,450, the female element is provided by a tubular connector body which has a window formed through its cylindrical wall, and a socket body which has an elastic claw wall protruding inwardly in the radial direction. The socket body is fitted onto the connector body, by moving the socket body from one of opposite sides of the connector body onto the connector body, such that the elastic claw wall of the socket body protrudes through the window of the connector body into a bore of the connector body. The elastic claw wall is brought into engagement with an annular swelling wall portion of the tubular male element, which is introduced into the bore of the connector body, whereby the connector body and the tubular male element are quickly connected to each other. For providing a fluid tightness between the male element and the connector body, an O-ring is provided to be fitted in the bore of the connector body. The O-ring is held by a bushing member which is formed independently of the connector body and the socket body and which is fitted in the bore of the connector body.
In this quick connector constructed as described above, the male element is introduced into the female element in which the socket body is fitted in an opening portion of the connecter body. This construction inevitably increases the diameter of the female element and accordingly increases the size of the entirety of the connector, causing a problem in installation of the connector which requires to be installed in a relatively narrow space. Further, the bushing member is provided to exclusively hold the O-ring or other elastic sealing ring member which is fitted in the bore of the connector body. The provision of the bushing member requires an additional step in the assembling process and also increases the number of the required components, resulting in an increased cost of manufacturing of the quick connector.
In a connector designed for connecting pipe of small diameter, which is disclosed in JP-A-08-210576, there is employed a construction in which a generally U-shaped slit is formed through a cylindrical wall of a connector body as the male element, whereby an elastic claw wall defined by the U-shaped slit is formed integrally with the connector body. The elastic claw wall is biased to be inclined inwardly in the radial direction of the connector body, so that an annular swelling wall of the male element (pipe) which is introduced into the connector body is brought into engagement with the elastic claw wall. However, this connector body having the construction, in which the elastic claw wall is biased to be inwardly inclined, has a configuration that is extremely difficult to be manufactured. It is considered that such a connector body is practically impossible to be produced in an injection molding operation that is very common to be practiced for efficiently producing a connector body. Even if such a connector body could be produced in an injection molding operation, it would be necessary to prepare a mold having an extremely complicated construction. Further, this connector includes a bushing member exclusively used to hold a sealing member which provides a fluid tightness between the connector body and the introduced pipe, for preventing the sealing member from coming off from the connector. The use of the bussing member problematically complicates the assembling process, deteriorates the efficiency of the manufacture, and increases the number of the required components, as in the above-described connector disclosed in JP-A-03-219189.
Further, JP-A-11-201355 discloses a quick connector including a tubular connector body (female element) and a holding member which has a generally C-shaped cross section and which is fitted in an axial end portion of the tubular connector body to be fixed to the tubular connector body. The holding member is brought into engagement with an annular protrusion portion formed in an outer circumferential surface of the male element in the form of a pipe, which is introduced into the holding member, so. that the connector body and the pipe are connected with each other. Owing to the cross sectional shape of the holding member, the tubular connector body, the holding member and the pipe are easily removable from each other, without using an releasing tool or other exclusive tool. However, this connector still has not provided a substantial solution to the problems encountered in the above-described two types of connectors.
That is, even in the construction of the connector disclosed in JP-A-11-201355, the diameter of the connector body is inevitably increased due to the introduction of the holding member in the axial end portion of the connector body, thereby still resulting in an increase in size of a connecting portion of the connector at which the connector is connected with the pipe. Further, in the interest of permitting the operation for removing the holding member from the connector body without using a releasing tool, the holding member is designed to protrude outwardly from the end portion of the connector body, thereby problematically increasing the (axial) length of the connector. Still further, this connector also requires, in addition to the holding member, another independent member in the form of a bushing member that is exclusively used to hold an O-ring as a sealing member, thereby complicating the assembling process and increasing the number of the components.
The present invention was developed under the above-described background situation. An object to be achieved by the present invention is to provide a quick connector which is capable of being more compact in its radial and longitudinal (axial) dimensions with a smaller -number of its components, than a conventional quick connector. Another object of the invention is to improve efficiencies of assembling and production of a quick connector with a reduced production cost, by reducing the number of the components.
The above technical object may be achieved according to the essence of the present invention, which provides a quick connector for providing a quick connection, characterized by comprising: (a) a tubular male element having an introduced end portion which straightly extends and which has an extreme end portion and an annular protrusion portion located rearwardly of and adjacently to the extreme end portion; and (b) a tubular female element having a first receiving portion and a second receiving portion which have respective tubular shapes configured to receive therein the annular protrusion portion and the extreme end portion of the introduced end- portion, respectively; wherein the first receiving portion extends from an axial end of the tubular female element toward the other axial end of the tubular female element, and has an axial hole into which the introduced end portion of the tubular male element is introduceable through an opening of the axial hole that is open in the axial end of the tubular female element; wherein the second receiving portion is located on one of opposite sides of the first receiving portion that is closer to the other axial end of the tubular female element than the other of the opposite sides of the first receiving portion such that the first and second receiving portions have a coaxial relation with each other; wherein the first receiving portion has a plurality of tongue portions each of which is elastically deformable and extends in a circumferential direction of the tubular female element, so as to prevent removal of the tubular male element from the axial hole when the introduced end portion of the tubular male element is introduced into the axial hole; wherein the first receiving portion has a plurality of beam portions which consist of respective parts of a cylindrical wall of the first receiving portion so as to be located on a same circle, and which extend in an axial direction of the tubular female element and are. spaced apart from each other by a predetermined spacing distance in the circumferential direction of the tubular female element; wherein each of the tongue portions is defined by a U-shaped slot which is formed through the cylindrical wall of the first receiving portion and which extends in a U-shaped manner from the corresponding one of the beam portions, such that the tongue portion extends from the corresponding beam portion in the circumferential direction over a distance not larger than the predetermined spacing distance; wherein each of the tongue portions has, in a free end portion thereof, an engaging protrusion portion which protrudes inwardly in a radial direction of the tubular female element so as to be brought into engagement with the annular protrusion portion of the introduced end portion of the tubular male element in a snap action manner; and wherein the engaging protrusion portion has, in an inner surface thereof, a guide surface whose diameter gradually reduces as viewed in a direction toward the other axial end of the tubular female element away from the axial end of the tubular female element.
In the quick connector constructed according to this invention, the tubular female element has the elastically deformable tongue portions formed integrally in its axially intermediate portion. The annular protrusion portion of the male element, which is introduced into the female element, is permitted by elastic deformation of the tongue portions, to climb over the engaging protrusion portions of the respective tongue portions, and is then brought into engagement with the tongue portions in a snap action manner. :Owing to the engagement of the annular protrusion portion of the male element with the tongue portions of the female element, the male element is connected to and held by the female element. This construction eliminates a member used for exclusively holding the male element, and accordingly makes the present connector to be compact in size with a smaller diameter of the female element and a smaller number of the required components, than a conventional connector having a construction in which an exclusive member is provided in the connector body as the female element into that the male element is introduced. Further, since each of the tongue portions is formed to extend in the circumferential direction, it is possible to avoid an increase in the axial length of the female element of the present connector due to the formation of the tongue portions.
Therefore, the quick connector according to the present invention can be compact in size with smaller diameter and (axial) length than those of the conventional quick connector, and accordingly makes it to possible to improve the efficiency of assembling or production of the connector with a reduced cost, owing to the reduced number of the required components.
Further, in the quick connector of the present invention, the engaging protrusion portion which is brought into engagement with the annular protrusion portion of the male element in a snap action manner has, in its inner surface, the guide surface whose diameter gradually reduces as viewed in the direction in which the male element is introduced into the axial hole of the female element. The guide surface is inclined with respect to the axis of the tubular female element such that a radial distance between the guide surface and the axis reduces as viewed in the abovedescribed direction in which the male element is introduced into the axial hole of the female element. Owing to this construction, the tongue portion can be elastically deformed so as to be then brought into engagement with the annular protrusion portion of the male element in a snap action manner, through a one-touch operation in which the introduced end portion of the male element is simply pushed into the axial hole of the female element. That is, the male element easily comes to be held by the female element, with a single movement of the male element and the female element toward each other. Thus, this construction advantageously facilitates the operation for connecting the male element with the female element, thereby permitting the connector to be more easy to operate.
The above-described technical object may be achieved according to the essence of the present invention, which provides a quick connector for providing a quick connection, characterized by comprising: (a) a tubular male element having an introduced end portion which straightly extends and which has an extreme end portion and an annular protrusion portion located rearwardly of and adjacently to the extreme end portion; (b) a tubular female element having a first receiving portion and a second receiving portion which have respective tubular shapes configured to receive therein the annular protrusion portion and the extreme end portion of the introduced end portion, respectively, and (c) an annular sealing member for assuring a fluid-tightness between the tubular male element and the tubular female element, wherein the first receiving portion extends from an axial end of the tubular female element toward the other axial end of the tubular female element, and has an axial hole into which the introduced end portion of the tubular male element is introduceable through an opening of the axial hole that is open in the axial end of the tubular female element; wherein the second receiving portion has an inner circumferential surface whose inside diameter is sufficiently larger than an outside diameter of the extreme end portion of the tubular male element, and is located on one of opposite sides of the first receiving portion that is closer to the other axial end of the tubular female element than the other of the opposite sides of the first receiving portion such that the first and second receiving portions have a coaxial relation with each other; wherein the tubular female element has an annular stop element which is located in an entrance portion of the second receiving portion and which protrudes radially inwardly from an inner circumferential surface of the entrance portion of the second receiving portion, the annular stop element having an inside diameter that is slightly larger than the outside diameter of the extreme end portion of the tubular male element, so that the annular stop element is opposed to the annular protrusion portion of the tubular male element so as to be brought into abutting-contact with the annular protrusion portion, for thereby limiting movement of the tubular male element toward the other axial end of the tubular female element away from the axial end of the tubular female element, when the introduced end portion of the tubular male element is introduced into the axial hole; wherein the tubular female element has a plurality of tongue portions which are provided in the first receiving portion, each of the tongue portions being elastically deformable and extends in a circumferential direction of the tubular female element, so as to prevent removal of the tubular male element from the axial hole when the introduced end portion of the tubular male element is introduced into the axial hole; wherein the first receiving portion has a plurality of beam portions which consist of respective parts of a cylindrical wall of the first receiving portion so as to be located on a same circle, and which extend in an axial direction of the tubular female element and are spaced apart from each other by a predetermined spacing distance in the circumferential direction of the tubular female element; wherein each of the tongue portions is defined by a U-shaped slot which is formed through the cylindrical wall of the first receiving portion and which extends in a U-shaped manner from the corresponding one of the beam portions, such that the tongue portion extends from the corresponding beam portion in the circumferential direction over a distance not larger than the predetermined spacing distance; wherein each of the tongue portions has, in a free end portion thereof, an engaging protrusion portion which protrudes inwardly in a radial direction of the tubular female element so as to be brought into engagement with the annular protrusion portion of the introduced end portion of the tubular male element in a snap action manner; wherein the engaging protrusion portion has, in an inner surface thereof, a guide surface whose diameter gradually reduces as viewed in a direction toward the other axial end of the tubular female element away from the axial end of the tubular female element; and wherein the sealing member is disposed on one of opposite sides of the annular stop element that is closer to the other axial end of the tubular female element than the other of the opposite sides of the annular stop element such that the sealing member is held in contact at an outer peripheral portion thereof with the inner circumferential surface of the second receiving portion, the sealing member being gripped between the extreme end portion of the tubular male element and the second receiving portion of the tubular female element when the introduced end portion of the tubular male element is introduced into the axial hole.
The quick connector according to the present invention has the male element which has the annular protrusion portion provided in its introduced end portion, and the female element which is configured to be capable of introducing therein the male element and which has the tongue portions that are formed integrally with the main body of the female element and that extend in the circumferential direction. The tongue portions of the female element are elastically deformable so as to be brought into engagement with the annular protrusion portion of the male element when the male element is introduced into the female element. Thus, this construction permits the connector to be compact in size with smaller diameter and (axial) length than those of the conventional quick connector, and accordingly makes it to possible to improve the efficiency of assembling or production of the connector with a reduced cost, owing to the reduced number of the required components.
In addition, the quick connector according to the present invention further includes the annular sealing member for providing a fluid tightness between the male element and the female element when the male element is introduced into the female element. The sealing member is disposed on a downstream side of the stop element that is provided in an inner wall of the second receiving portion, as viewed in the direction in which the male element is introduced into the female element. Thus, the sealing member can be effectively held in position by abutting-contact of the sealing member with the stop element, for example, when the male element is pulled out of the female element.
The above-described technical object may be achieved according to the essence of the present invention, which provides The above-described technical object may be achieved according to the essence of the present invention, which provides a quick connector for providing a quick connection, characterized by comprising: (a) a tubular male element having an introduced end portion which straightly extends and which has an extreme end portion and an annular protrusion portion located rearwardly of and adjacently to the extreme end portion; (b) a tubular female element having a first receiving portion and a second receiving portion which have respective tubular shapes configured to receive therein the annular protrusion portion and the extreme end portion of the introduced end portion, respectively, and (c) an annular sealing member for assuring a fluid-tightness between the tubular male element and the tubular female element, wherein the first receiving portion extends from an axial end of the tubular female element toward the other axial end of the tubular female element, and has an axial hole into which the introduced end portion of the tubular male element is introduceable through an opening of the axial hole that is open in the axial end of the tubular female element; wherein the second receiving portion has an inner circumferential surface whose inside diameter is sufficiently larger than an outside diameter of the extreme end portion of the tubular male element, and is located on one of opposite sides of the first receiving portion that is closer to the other axial end of the tubular female element than the other of the opposite sides of the first receiving portion such that the first and second receiving portions have a coaxial relation with each other; wherein the tubular female element has an annular stop element which is located in an entrance portion of the second receiving portion and which protrudes radially inwardly from an inner circumferential surface of the entrance portion of the second receiving portion, the annular stop element having a radially-extending annular surface and an inside diameter that is slightly larger than the outside diameter of the extreme end portion of the tubular male element, so that the annular stop element is opposed to the annular protrusion portion of the tubular male element so as to be brought into abutting-contact with the annular protrusion portion, for thereby limiting movement of the tubular male element toward the other axial end of the tubular female element away from the axial end of the tubular female element, when the introduced end portion of the tubular male element is introduced into the axial hole; wherein the tubular female element has a plurality of tongue portions which are provided in the first receiving portion, each of the tongue portions being elastically deformable and extends in a circumferential direction of the tubular female element, so as to prevent removal of the tubular male element from the axial hole when the introduced end portion of the tubular male element is introduced into the axial hole; wherein the first receiving portion has a plurality of beam portions which consist of respective parts of a cylindrical wall of the first receiving portion so as to be located on a same circle, and which extend in an axial direction of the tubular female element and are spaced apart from each other by a predetermined spacing distance in the circumferential direction of the tubular female element; wherein each of the tongue portions is defined by a U-shaped slot which is formed through the cylindrical wall of the first receiving portion and which extends in a U-shaped manner from the corresponding one of the beam portions, such that the tongue portion extends from the corresponding beam portion in the circumferential direction over a distance not larger than the predetermined spacing distance; wherein each of the tongue portions has, in a free end portion thereof, an engaging protrusion portion which protrudes inwardly in a radial direction of the tubular female element so as to be brought into engagement with the annular protrusion portion of the introduced end portion of the tubular male element in a snap action manner; wherein the engaging protrusion portion has, in an inner surface thereof, a guide surface whose diameter gradually reduces as viewed in a direction toward the other axial end of the tubular female element away from the axial end of the tubular female element; and wherein the sealing member is disposed on one of opposite sides of the annular stop element that is closer to the other axial end of the tubular female element than the other of the opposite sides of the annular stop element such that the sealing member is held in contact at an outer peripheral portion thereof with the inner circumferential surface of the second receiving portion, the sealing member being gripped between the extreme end portion of the tubular male element and the second receiving portion of the tubular female element when the introduced end portion of the tubular male element is introduced into the axial hole.
In the quick connector according to the present invention, too, the number of the required components and the radial and axial dimensions of the connector are made smaller than in conventional various types of connectors, resulting in an improved efficiency of assembling or production of the connector with a reduced cost.
In the quick connector according to the present invention, where the connector includes the annular sealing member for assuring a fluid-tightness between the male element and female element, an O-ring is preferably used as the sealing member.
According to a preferred form of the quick connector according to the present invention, the U-shaped slot has a first slot part which is formed between a side face of the tongue portion that is closer to the axial end of the tubular female element than the other side face of the tongue portion, and a first slot defining face that is formed in the cylindrical wall of the first receiving portion and that is opposed to the side face of the tongue portion, the first slot part extending in the circumferential direction of the tubular female element; wherein the tubular female element has a first restricting protrusion which is provided in one of the free end portion of the tongue portion and an opposed portion of the first slot defining face opposed to the free end portion, and which protrudes into the first slot part; and wherein the tubular female element has a first recess portion which is provided in one of the free end portion of the tongue portion and the opposed portion of the first slot defining face, so that the first restricting protrusion is superposed on the first recess portion in the radial direction so as to be brought into engagement with the first recess portion, when the free end portion of the tongue portion is forced by the annular protrusion portion of the tubular male element to be displaced in a direction that causes the tubular male element to be pulled out of the tubular female element, upon application of a pulling force between the tubular male element and the tubular female element.
This construction prevents the tongue portion (the engaging protrusion portion) and the male element (the annular protrusion) from being easily disengaged from each other, even when at least one of the male element and the female element is forced in a direction that causes the male element to be pulled out of the male element. That is, the construction prevents the tongue portion from being displaced outwardly in the radial direction of the female element, when the pulling force acts between the male element and the female element. Thus, the linkage or connection of the male element with the female element is maintained with an increased reliability.
According to another preferred form of the quick connector according to the present invention, the tubular female element has a second restricting protrusion which extends across the U-shaped slot, from one of the free end portion of the tongue portion and an opposed portion of a slot defining face that is formed in the cylindrical wall of the first receiving portion and that is opposed to the free end portion of the tongue portion; and wherein the tubular female element has a second recess portion which is provided in one of the free end portion of the tongue portion and the opposed portion of the slot defining face, such that the second restricting protrusion and the second recess portion are superposed on each other with a predetermined radial spacing distance therebetween in the redial direction, for thereby preventing the free end portion of the tongue portion from being displaced outwardly in the radial direction over a distance not smaller than the predetermined radial spacing distance.
In the thus constructed quick connector, the second restricting protrusion and the second recess portion, which are superposed on each other in the radial direction, may be adapted to be brought into contact with each other as a result of radially outward deformation of the tongue portion, for example, when the annular protrusion portion of the male element climbs over the engaging protrusion portion of the tongue portion. Thus, it is possible to prevent the tongue portion from being deformed outwardly in the radial direction in an excessive amount which is larger than an amount required for the annular protrusion portion of the male element to climb: over the engaging protrusion portion of the tongue portion.
Thus, in the connector according to the present invention, when the male element held by the female element is pulled out of the female element by the elastic deformation of the tongue portion in the radially outward direction, the tongue portion is prevented from being deformed in the excessive amount larger than the required amount, thereby effectively preventing the tongue portion from being damaged or broken.
According to still another preferred form of the quick connector according to the present invention, the U-shaped slot has a second slot part which is formed between the annular surface of the annular stop element and a side face of the tongue portion that is closer to the other axial end of the tubular female element than the other side face of the tongue portion, the second slot part extending in the circumferential direction of the tubular female element; and wherein the tubular female element has a third restricting protrusion which protrudes into the second slot part, from one of a portion of the side face of the tongue portion that is located in the free end portion, and a portion of the annular surface of the annular stop element that is opposed to the portion of the side face of the tongue portion, for thereby limiting displacement of the free end portion of the tongue portion toward the other axial end of the tubular female element, upon introduction of the introduced end portion of the tubular male element into the axial hole of the tubular female element.
When the annular protrusion of the introduced male element is intended to climb over the engaging protrusion portion of the tongue portion, the tongue portion is forced in the direction in which the male element is introduced into the female element. In the construction of this preferred form of the quick connector of the invention, the third restricting protrusion protruding from the above-described one of the portion of the side face of the tongue portion and the portion of the annular surface of the annular stop element is brought into contact with the other of the portion of the side face of the tongue portion and the portion of the annular surface of the annular stop element, for thereby effectively preventing the tongue portion from being excessively deformed, increasing a durability of the tongue portion and making it possible to repeat an operation for introducing the male element into the female element.
The quick connector according to the present invention preferably has a construction in which the tubular female element includes a first tubular member having axially opposite end portions one of which is provided by the first receiving portion, a second tubular member having axially opposite end portions one of which is provided by the second receiving portion, and connecting means for connecting the first and second tubular members such that the first tubular member is connected at the other of the axially opposite end portions thereof to the second receiving portion of the second tubular member, with a coaxial relationship between the first and second tubular members.
In the quick connector having the above construction, it is preferable to employ an arrangement in which the connecting means is constituted by a fitting hole which is formed in an entrance portion of the above-described one of the axially opposite end portions of the second tubular member, and the annular stop element which is provided in the other of the axially opposite portions of the first tubular member and which is fitted in the fitting hole. Further, in the quick connector having the above construction, it is advantageous to employ, in addition to or in place of the above arrangement, another arrangement in which the connecting means is constituted by an engaging portion which is formed in an outer circumferential surface of an entrance portion of the second receiving portion that is included in the above-described one of the axially opposite end portions of the second tubular member, and an engaging arm which extends from an outer circumferential surface of the annular stop element provided in the other of the axially opposite portions of the first tubular member toward the other of the axially opposite end portions of the second tubular member and which is brought into engagement with the engaging portion.
Each of the above arrangements is effective to simplify a connecting construction required for the firm connection of the two members which constitute the female element, facilitate an operation for connecting the two tubular members, and minimize an increase in the axial length of the connector due to the connecting construction.
According to still another preferred form of the quick connector according to the present invention, the tubular female element is provided by a single piece which is formed of a thermosetting resin material through a molding operation, for thereby further reducing the number of the required components of the quick connector. The further reduction in the number of the required components leads to a further improvement in the efficiency of assembling or production of the connector with a further reduced cost.
According to still another preferred form of the quick connector according to the present invention, each of the tongue portions has a width and/or a thickness that reduces as viewed in a direction toward the free end portion thereof away from a proximal end portion thereof at which the tongue portion is connected to the cylindrical wall portion of the first tubular member. The arrangement according to this preferred form of the connector is effective to prevent a local stress concentration in the proximal end portion of the tongue portion, thereby increasing a durability of the tongue portion.
According to still another preferred form of the quick connector according to the present invention, each of the tongue portions has an operating portion which protrudes radially outwardly from an outer circumferential surface of the free end portion. The provision of the operating portion facilitates an operation for removing the male element from the female element. That is, the tongue portion can be easily deformed outwardly in the radial direction, by simply forcing the operating portion outwardly in the radial direction, so that the engagement of the annular protrusion portion of the male element with the engaging protrusion portion of the tongue portion is easily released.
For achieving the above-described object, the quick connector according to the invention preferably comprises: a tubular male element having an annular protrusion portion provided on an outer circumferential surface of an introduced end portion of the tubular male element; and a female element having a tubular housing, wherein the tubular housing has an annular portion in one of axially opposite end portions thereof, through which the tubular male element is introduced into the tubular housing; a fitting end portion in the other of the axially opposite end portions thereof, onto which a tube is to be fitted so as to be fixed to the tubular housing; and an elastically deformable tongue portion which is formed by cutting through a cylindrical wall of an axially intermediate portion of the tubular housing and which extends in a circumferential direction of the tubular housing; wherein the tongue portion has a free end portion and a proximal end portion in one and the other of circumferentially opposite end portions thereof, respectively; and wherein the tongue portion has an engaging protrusion portion which is provided in an inner surface of the free end portion and which protrudes inwardly in a radial direction of the tubular housing, the tongue portion being deformed for permitting the annular protrusion portion of the male element to climb over the engaging protrusion portion upon introduction of the male element into the tubular housing, whereby the annular protrusion of the male element is brought into engagement with the engaging protrusion portion of the tongue portion.
In the quick connector in which the above-described construction is employed, the tubular female element has the elastically deformable tongue portion formed integrally in its axially intermediate portion. The tongue portion is deformable for permitting the annular protrusion portion of the male element to climb over the engaging protrusion portion of the tongue portion, upon introduction of the male element into the tubular housing, whereby the annular protrusion portion of the male element is brought into engagement with the engaging protrusion portion of the tongue portion in a snap action manner. Thus, the male element is connected with the female element and is held by the female element, with the engagement of the annular protrusion portion of the male element with the engaging protrusion portion of the tongue portion. This construction eliminates a member used for exclusively holding the male element, and accordingly makes the connector to be compact in size with a smaller diameter and a smaller number of the required components, as compared with a conventional connector having an exclusive member which is provided for holding the male element. Further, since each of the tongue portions is formed to extend in the circumferential direction, it is possible to avoid an increase in the axial length of the female element of the present connector due to the formation of the tongue portions.
Therefore, the quick connector according to the present invention can be compact in size with smaller diameter and (axial) length than those of the conventional quick connector, and accordingly makes it to possible to improve the efficiency of assembling or production of the connector with a reduced cost, owing to the reduced number of the required components.
For achieving the above-described object, the quick connector according to the invention preferably comprises: a tubular male element having an annular protrusion portion which is provided on an outer circumferential surface of an introduced end portion of the male element and which is spaced apart from an axial end of the male element by a predetermined distance; and a tubular female element having an opening end portion in one of axially opposite end portions thereof, through which the tubular male element is introduced into the tubular female element so as to be fixed to the tubular female element, wherein the tubular female element further having an annular portion which is provided in at least one of the axially opposite end portions and which extends continuously in a circumferential direction of the tubular female element; wherein the female element is constituted by a first tubular member which provides the opening end portion through that the introduced end portion of the male element is introduced, and a second tubular member which is connected to the annular portion of the first tubular member by connecting means such that the first and second tubular members have a coaxial relationship therebetween; wherein the second tubular member has a shoulder surface in its inner surface, so as to have a large diameter portion at which the second tubular member is connected with the first tubular member; wherein the connector further comprises an annular sealing member which is fitted in the inner surface of the large diameter portion; wherein the first tubular member has a plurality of integrally formed, elastically deformable tongue portions each of which is formed by cutting through a cylindrical wall of the first tubular member and each of which extends in a circumferential direction of the tubular housing; wherein the tongue portion has a free end portion and a proximal end portion in one and the other of circumferentially opposite end portions thereof, respectively; wherein the tongue portion has an engaging protrusion portion which is provided in an inner surface of the free end portion and which protrudes inwardly in a radial direction of the first tubular member, the tongue portion being deformed for permitting the annular protrusion portion of the male element to climb over the engaging protrusion portion upon introduction of the male element into the female element, whereby the annular protrusion of the male element is brought into engagement with the engaging protrusion portion of the tongue portion; wherein the first tubular member has a sealing-member stop portion in an axial end portion thereof at which the first tubular member is connected with the second tubular member, the sealing-member stop portion having a radially inner end which is distant from the axis of the female element by a radial distance smaller than a radius of the inner circumferential surface of the large diameter portion of the second tubular member; and wherein the annular sealing member, which is fitted in the large diameter portion, is interposed between the shoulder surface and the sealing-member stop portion as a result of the connection of the first and second tubular members, and is fluid-tightly gripped by and between the second tubular member and a portion of the outer circumferential surface of the tubular male member which portion is closer to the axial end of the tubular male member than the annular protrusion portion when the tubular member is introduced into the tubular housing body.
In the thus constructed quick connector, the first and second tubular members constituting the female element are connected at their respective axially end portions, in contrast to the arrangement in the conventional connector in which two members are connected with each other such that the two members are superposed on each other at their respective axially end portions, or such that one of the two members is completely mounted on or introduced in the other member. Therefore, it is possible to avoid an increase in the diameter of the female element. It is also possible to minimize the (axial) length of the female element, since the female element of the present connector does not require an axially protruding portion which would be required if one of the two tubular members were mounted on or introduced in the other tubular member. Thus, the present connector can be advantageously made compact in size, with minimized diameter and axial length thereof.
In the construction of the quick connector according to the present invention, the female element is constituted by the two tubular members. The plurality of tongue portions are provided in one of the two tubular members so as to be formed integrally with the tubular member, for engaging the introduced male element. The stepped inner circumferential surface in which the sealing member is fixed is provided in the other of the two tubular members. This construction is effective to simplify the configuration of each of the two tubular members, making it possible to easily produce each of tubular members, for example, in an injection molding operation, thereby improving the efficiency of production or manufacture of the connector, even where the tongue portions are designed to protrude into the bore of the corresponding one of the two tubular members.
Further, in the quick connector of the present invention, the sealing-member stop portion is provided in one of the two tubular members so as to be formed integrally with the tubular member. The sealing member, which is provided in the other of the two tubular members, is prevented by the sealing-member stop portion, from being pulled out of the other tubular member. This arrangement eliminates a bushing member or other member exclusively used to hold the sealing member, and also eliminates a conventionally required cumbersome operation for fitting such an exclusive member in a predetermined position, whereby the production efficiency and cost of the present connector are remarkably improved and lowered, respectively.